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51.
A class of topological excitations-the odd-winding number vortices-in a spinless 2D chiral p-wave (px+ipy) superconductor traps Majorana fermion states in the vortex cores. For a dilute gas of such vortices, the lowest energy fermionic eigenstates are intrinsically nonlocal. We predict two testable signatures of this unusual quantum nonlocality in quasiparticle tunneling experiments. We discuss why the associated teleportationlike phenomenon does not imply the violation of causality.  相似文献   
52.
In what follows, I reply to the preceding article by Michel Janssen and Robert Schulmann, which itself was a response to my article on One month in the history of the discovery of general relativity theory, published in the February 1998 issue of this journal. I stand by the historical analysis and conclusions presented in my original article.  相似文献   
53.
Potentiometric studies of the mixed ligand derivatives of 11-Th(IV)—DTPA chelate (whereDTPA=diethylene-triamine pentaacetic acid) with certain secondary ligands, such as lactic, mandelic and o-hydroxynaphthoic acids have been carried out. The pH-titrations of the reaction mixtures containing 111 molar ratio of metal ion toDTPA to secondary ligand have shown the formation of 111 ternary complexes at higher pH (8). The equilibrium constants of the resulting mixed complexes have been determined at 30±1°C and =0.1 (KNO3) and the order of stability in terms of secondary ligands has been found to be o-hydroxy naphthoic acids>mandelic acid>lactic acid.  相似文献   
54.
Molecular Diversity - Wnt signaling pathway is an evolutionarily conserved pathway responsible for neurogenesis, axon outgrowth, neuronal polarity, synapse formation, and maintenance....  相似文献   
55.
We report neutron scattering experiments probing the influence of uniaxial strain on both the magnetic and structural order parameters in the parent iron pnictide compound, BaFe2As2. Our data show that modest strain fields along the in-plane orthorhombic b axis can affect significant changes in phase behavior simultaneous to the removal of structural twinning effects. As a result, we demonstrate in BaFe2As2 samples detwinned via uniaxial strain that the in-plane C4 symmetry is broken by both the structural lattice distortion and long-range spin ordering at temperatures far above the nominal (strain-free) phase transition temperatures. Surprising changes in the magnetic order parameter of this system under relatively small strain fields also suggest the inherent presence of magnetic domains fluctuating above the strain-free ordering temperature in this material.  相似文献   
56.
The magnetic properties of three samples of Fe3Al—as melted and annealed, high energy ball milled and milled sample followed by annealing—have been studied using a combination of X-ray diffraction, Transmission electron microscopy, room temperature 57Fe M?ssbauer spectroscopy and DC magnetization. The different magnetic contributions in the M?ssbauer spectra have been explained in terms of the nearest neighbour Al configuration of Fe. These correlate well to the bulk magnetic properties determined by DC magnetization. High temperature DC magnetization studies show the presence of antiferromagnetic contributions from grain boundaries in the ball milled, nano sized sample.  相似文献   
57.
11 and 12 molar reactions of dioxouranium(VI) acetate dihydrate with the monobasic bidentateSchiff bases,o-HOC6H4CH=NR oro-HOC10H6CH=NR (R=C2H5,n-C3H7,n-C4H9 or C6H5) and bibasic tridentateSchiff bases,o-HOC6H4CH=NR(OH) oro-HOC10H6CH=NR(OH) (R=–CH2CH(CH3)- or —CH2CH2CH2–) have been studied and derivates of the type UO2(OAc)2(SBH), UO2(OAc)2(SBH)2, UO2(OAc)2(SBH 2) and UO2(OAc)2(SBH 2)2 (whereSBH andSBH 2 represent monobasic bidentate and bibasic tridentateSchiff base molecules respectively) have been isolated. These have been characterized by elemental analysis, conductance measurements and IR spectral studies.
UO2 2+-Komplexe von Schiff-Basen. VII. Uranylacetat-Komplexe mit monobasischen zweizähnigen und bibasischen dreizähnigen Schiff-Basen
Zusammenfassung Es wurden in 1:1- und 1:2-molaren Reaktionen von UO2(OAc)2·2H2O mitSchiff-Basen (L) Komplexe des Typs UO2(OAc)2 L bzw. UO2(OAc)2 L 2 isoliert. Die Komplexe wurden mittels Elementaranalyse, Leitfähigkeitsmessungen und IR-Spektren untersucht.
  相似文献   
58.
We consider quantum Hall states at even-denominator filling fractions, especially nu=5/2, in the limit of small Zeeman energy. Assuming that a paired quantum Hall state forms, we study spin ordering and its interplay with pairing. We give numerical evidence that at nu=5/2 an incompressible ground state will exhibit spontaneous ferromagnetism. The Ginzburg-Landau (GL) theory for the spin degrees of freedom of paired Hall states is a perturbed CP2 model. We compute the coefficients in the GL theory by a BCS Stoner mean-field theory for coexisting order parameters, and show that even if repulsion is smaller than that required for a Stoner instability, ferromagnetic fluctuations can induce a partially or fully polarized superconducting state.  相似文献   
59.
The fabrication of high quality thin films of poly (vinylidene fluoride) embedded with multiwalled carbon nanotubes using pulsed laser deposition technique is reported. The prepared films were characterized for structural, morphology and dielectric properties. The morphology analysis revealed uniform dispersion of multiwalled carbon nanotubes throughout the polymer matrix. X-ray diffraction results suggested that the poly (vinylidene fluoride) film is in amorphous phase while addition of multiwalled carbon nanotubes showed presence of crystalline peaks in the nanocomposites films. It was interesting to note that the nanocomposite films exhibits significant enhancement of the ferroelectric β-phase as evidenced by the X-ray diffraction and Fourier transform infrared spectroscopy results. The dielectric analysis shows a remarkable enhancement in the dielectric permittivity of nanocomposites with lower loss and conductivity level. The results can be attributed to the formation of minicapacitor network and relatively higher percolation threshold in the nanocomposites.  相似文献   
60.
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